What is a Certified Kubernetes Administrator (CKA)?
As containers in a cloud-native world are increasingly getting mainstream, Kubernetes continues to see wider adoption. And why not? Alongside being a feature-rich platform for container orchestration, Kubernetes has an extensive ecosystem of tools and community support that continues to expand. While Kubernetes’ adoption continues to grow, so does the demand in acquiring developer skills, which promises an eventful career for those who have a passion for technology.
The Certified Kubernetes Administrator (CKA) is one such developer upskilling program that is managed by the Linux and Cloud Native Computing Foundations to help standardize required skills to administer Kubernetes. At the end of the program, the aspiring candidate takes an exam to earn the CKA certificate that establishes his credibility and knowledge of the Kubernetes platform.
This article is an all-inclusive guide to the CKA program, that includes its curriculum and study-guide broken into specific domains. While doing so, we also include tips for exam success as well as highlighting some of the best available online resources that one may make use of.
The 2021 CKA curriculum
The updated curriculum for the CKA program is available on the official CNCF/Linux foundation website. The study guide outlines every subtopic under each domain, and what percentage of the total exam score each domain will cover. It is important to go through the guide as it helps candidates estimate their current knowledge and the gaps that need to be addressed.
The high-level breakdown of the exam, as indicated in the latest study guide, is as shown:
|Cluster Architecture, Installation & Configuration||25%|
|Workloads & Scheduling||15%|
|Services & Networking||20%|
CKA exam details
The CKA exam is a performance-based, proctored practical test that requires the candidate to solve multiple cluster-related tasks from a simulated command line. The exam lasts 120 Minutes and consists of between 15 and 20 tasks. This exam environment can be accessed from any computer with chrome/chromium installed, as long as other exam requirements of systems and locations are met.
The exam environment consists of up to six different clusters running under one master and several worker nodes. Registration for the exam costs $300 and one retake is allowed. You will need to score at least 66% to earn a pass. Click here to register for the exam. You will need a Linux Foundation ID to register for the CKA Exam.
CKA study guide
Cluster Architecture, Configuration & Installation
This is the basic Getting Started section of the CKA program and therefore carries the most weightage of 25%. This section focuses on setting up a Kubernetes cluster as well as provisioning the infrastructure it will run on. Additionally, installing a Kubernetes cluster and upgrading with kubeadm will be the main focus for this section. Other areas of study in this domain include Cluster Architecture, High Availability Cluster Setup, Backup using ETCD, Backup & Restore with
kubeadm, and setting up Role-Based Access Controls (RBAC).
There are plenty of installation and configuration options available within Kubernetes, and the exam may test familiarity with several. It is strongly advised to get acquainted with the various tools as described in the Kubernetes Setup Documentation.
Workloads & Scheduling
As a Kubernetes administrator, it is important to understand how containerized workloads are hosted and distributed among various nodes within a cluster. Carrying 15% of the total exam weightage, this section of the CKA program explores the basics of cluster resource creation and management alongside Kubernetes Deployments and POD Scheduling. With adequate knowledge and practice of this section, a candidate can -
- Create an application deployment
- Perform updates and rollbacks
- Configure applications using secrets
- Use configMaps for storing object configurations
- Scale applications
- Schedule PODs
- Explore Kubernetes Primitives
- Create templates and manifests.
Networking & Services
Constituting 20% of the total score, this section requires thorough practical learning as it explores how communication is established between different application components using services. This section delves into POD and Service Networking concepts that prepare the administrator to perform various network configuration tasks for cluster nodes.
Some of the topics included as part of this section include -
- Load Balancer
- Ingress Controllers
- Core DNS
- Container Network Interface (CNI) Plugins
Containers are ephemeral in nature, meaning they terminate after the process they are running stops. This means data could be lost every time a process terminates. Kubernetes offers Storage Volumes to help persist data so that it is not dependent on the container lifecycle. To help the candidate appearing for the CKA exam get a firm grasp of how storage is managed in a Kubernetes cluster, this section carries 10% of the total exam score and covers concepts dedicated to creating and managing storage volumes.
As part of the storage domain, the following topics are covered:
- Storage Classes
- Persistent Volumes and Persistent Volume Claims
- Volume Modes
- Access Modes
- Volume Reclaim Policies
- Configuring Applications with Persistent Storage
Troubleshooting cluster issues make up the largest portion of Kubernetes Administrative tasks. As a result, this section carries the maximum weightage of 30% in the CKA test.
As with any programming environment, applications running in Kubernetes typically experience installation or runtime errors. This section is dedicated to the tools and practices used for diagnosing errors in Kubernetes clusters and applications.
As a future Kubernetes Administrator, it is important to get familiar with
- Cluster & Node logging
- Kubernetes monitoring
- Managing logs
- Troubleshooting networks and cluster components
- Managing application failure.
There are plenty of courses, tutorials, and books available to help anyone get ready for the CKA exam. It is recommended to try different resources to get a broader experience of Kubernetes Cluster Administration.
Here are a few available resources for both continuing and aspiring Kubernetes Administrators.
Hands-on Practice Labs & Playgrounds
As CKA is a highly practical and performance-based test, it is important to get acquainted with running clusters in a hands-on setup. There are several online labs and practice environments where the candidate can run clusters in a production-like setup. These include:
- The Katacoda playground
- Kubernetes Tasks
- Google Cloud GKE
- Amazon’s AWS EKS
- Microsoft Azure’s Managed Kubernetes Service
These services allow the candidate to practice commands and deployments on managed Kubernetes clusters.
Kubernetes books and courses
While the CKA exam can be a self-paced study, it is easier to enroll in a course that covers the domain topics in a structured manner. This also helps since the course administrators can respond personally to concerns that may arise during practice.
A few popular courses available for CKA exam preparation include:
- Kode Kloud’s Certified Kubernetes Administrator (CKA) with Practice Tests (Paid)
- Udemy Certified Kubernetes Administrator (CKA) with Practice Tests (Paid)
- The Linux Foundation Kubernetes Fundamentals (LFS258) (Paid)
- Pluralisight’s Path to Certified Kubernetes Administrator (Free Trial)
Books are considered a great source of self-learning that goes in-depth of cluster administration. Some of these include:
- Kubernetes up and running
- Kubernetes in Action
- Kubernetes Best Practices: Blueprints for Building Successful Applications on Kubernetes
- The Complete Kubernetes Guide: Become an expert in container management with the power of Kubernetes
Other resources include pre-optimized clusters for self-learning. These allow the candidate to work through tasks in a guided environment using already provisioned cluster resources. Some of these cluster playgrounds include:
- Kubernetes the hard way by Kelsey Hightower
- The Katacoda Kubernetes Course
- The CKA Practice Environment
CKA preparation self learning tips
Though CKA allows a candidate one retake of the test, it is advised to prepare well to pass in the first take. Some useful tips when studying and preparing for the CKA exam include:
- Get acquainted with the Linux Command Line and Docker as the majority of Kubernetes tasks are based upon them.
- Adequately practice using mock exams and online playgrounds to understand the exam environment - this will help manage time and stress during the exam.
- Have a fixed study schedule to develop a routine of working with Kubernetes.
- Read through and understand the latest Kubernetes Documentation and Updates as you prepare for the exam.
- Have registration and identification details ready days in advance of the test to avoid last-minute panic.
By managing containerized applications in how efficiently they operate, Kubernetes acts as an essential enabler to a DevOps model. With the growth of Cloud and DevOps, there is a relatively growing demand for Kubernetes and its skilled workforce.
Professionals who are thinking about working with Kubernetes, or those who are already working on K8s production clusters, taking the CKA certification is highly recommended. This article introduced CKA certification details, curriculum breakdown, and essential resources that candidates can use to prepare for the exam.
Let us know your experience with taking the CKA test, and if you have tips or resources to share for the benefit of others taking the test.